Semiconductor manufacturing is a complex process, from design to fabrication. For example, in order to manufacture a semiconductor device, many processes must be performed in order to obtain a desired design (pattern or structure) on the wafer. These processes range from initial design of the circuit or other structure, to the deposition of material, lithography and etching processes which form the circuit or other structure.
Lithography processes, for example, include the use of optical masks in order to print patterns on a wafer. These patterns define the structure of and interconnection between the different components and features of the integrated circuit. The mask includes, for example, patterns of different shapes, which can be transferred to an entire wafer in a single exposure.